Mine will have been installed three years in two weeks time.
For some balance, I have had not one single problem with the CS92 - I literally haven't touched it since the day it was installed (still on the original batteries too).
Several people have posted about comms errors with the CS92 here, and yet again this morning no hot water because of a comms error that occurred at 3am and wasn't resolved until batteries were taken out and reinstated at 6.50am.
I've tried the method of making sure the contacts on the back of the pcb are sound. The sensor is nowhere near any metal or wires, and it is in the next room to the controller and gets an excellent signal.
This is plain and simple an error in the software used by the CS92 and or the controller.
Quite frankly when Honeywell can spend their time adding pretty pictures of flames to the screen to tell you when the boiler is firing or hot water is on, but keep silent on the fact the CS92 has an inherent fault and not bother updating it, it tells me all I need to know about their attitude to the product.
Come the spring I'll most likely be removing the hot water function from Evohome and reverting back to a fixed timer and a smart controlled immersion heater. Honeywell have known about this issue for years and simply ignored it.
I shall also be doing research on other smart heating controls and or zwave controlled radiator valves with a view to ripping the entire Evohome system out.
I've been an advocate of Evohome and demonstrated it's benefits to any visitors to the home that ask about the controller when they see it sat on the side, but no longer. This is just pathetic.
Mine will have been installed three years in two weeks time.
For some balance, I have had not one single problem with the CS92 - I literally haven't touched it since the day it was installed (still on the original batteries too).
Have installed hundreds, and have not had any reports of this fault.
If it was a software error I think I would have noticed.
Kind Regards - Dan Robinson (Jennings Heating Ltd)
Clearly I, and the others reporting this fault on various threads here are making it up then.
Just because the issue is not common does not negate its existence. Perhaps the number of heating cycles we have for our hot water just makes it more likely that an intermittent comms fault from the CS92 will coincide with one. If users have other systems controlling their hot water like evotouch or similar, or use the hot water element of evohome to report temps or as a booster, then they will likely never see the problem. There is enough of an evidence base here to suggest that there is a problem with either the software or hardware of the CS92, especially when people are reporting issues fixed by taking it apart and bending contacts (which has not resolved it in my case and several others below).
I will however concede that it is probably not common enough to make it commercially viable enough to look into. Though this issue along with the complete lack of innovation on range extenders for installations in larger environments is starting to make me think that whilst a good product, the Evohome range is not being given the attention it needs at Honeywell. Issues like this will be the reason that consumer like me look at other options in the future when individual room controll becomes available from other manufacturers. At £3k+ invested in Evohome its going to be a big outlay to swap, but trust me, when the wife complains at 6.30 am that the hot water isn't working again, swapping out a £3k system to solve the problem seems a bargain.
http://www.automatedhome.co.uk/vbull...ll=1#post33880
http://www.automatedhome.co.uk/vbull...ll=1#post33881
http://www.automatedhome.co.uk/vbull...ll=1#post33884
http://www.automatedhome.co.uk/vbull...ll=1#post33885
http://www.automatedhome.co.uk/vbull...ll=1#post35698
http://www.automatedhome.co.uk/vbull...ll=1#post32574
http://www.automatedhome.co.uk/vbull...ll=1#post32751
Last edited by Cchris; 6th March 2018 at 09:59 AM.
So no reports of hot water overshoots then ? How would you know ?
If a customer has their hot water set to 55 degrees and it sometimes heats to 60 degrees due to comms errors, are they going to phone you to complain about it ? I suspect in the majority of cases, no. Some people wouldn't even notice or even know what their hot water was set to in the first place or think some variation was normal.
The nature of the fault is that it can be there at a low level (intermittent comms loss, moderate hot water overshoots) without being bad enough to trigger a big scary red warning on the screen that might prompt a customer to phone you.
The controller has to hear nothing from the CS92A for three hours before it will report a fault... that is a lot of lost comms transmissions...
Living with the system day in day out and observing its intermittent behaviour is a little different to installing it for customers who you seldom hear back from and aren't probably as technical or discerning of minor issues as yourself. So if you have not experienced this issue in your own home installation you may not even appreciate what all the fuss is about.
For those of us who have experienced this problem it is a very real, very frustrating problem with no real solution other than to ditch Evohome. I like the system as a whole enough to stick with it but the intermittent hot water issues are frustrating to say the least, especially when it results in uncomfortably hot water.
Last edited by DBMandrake; 6th March 2018 at 10:34 AM.
I thought when you checked your Domoticz logs a while ago you saw evidence of hot water overshoots ?
Or do you just mean you haven't had any cases of hot water failing to heat up at all or comms errors reported on the controller fault log ?
If so, I think the latter is just an extreme case of the same root comms issues. Minor comms issues can result in overshoots, major comms issues can result in a reported comms error on the controller which then causes the hot water relay to be kept off for safety reasons.
It would be interesting to see the fault logs of other users with the CS92 to see if they are experiencing comms faults, but they just haven't happened to coincide with heating demand times and therefor have not caused a noticeable problem.
I have two choices to try and fix this as far as I can see:
1. Replace the CS92 and hope that i just happen to have a faulty one, and replacement will fix it. Cost £80ish.
2. Rig up a mains 3v power supply on a 7 day timer set to disconnect and reconnect the power for a minute just before each heating cycle - mimicking the removal and reinsertion of the batteries which invariably fixes the problem every single time. Cost around £15.
If a simple removal and reinsertion of the batteries forces an immediate update, then this seems like a problem that is caused by and could very easily be fixed with different software or method of interaction between the CS92 and the controller. The batteries in a HR92 seem to last around a year, with constant polling, and the duty of driving a motor a few times a day. So why is the CS92 designed in such a way that it can't send and receive more regular temperature settings/instructions and effectively "reboot" itself if it misses one or more? Why is it allowed to go three hours or more without talking to a controller without taking some corrective action itself?
Agreed. I have given up worrying about my CS92 and accept that there are regular overshoots, mainly in the winter. Because my DHW valve is wired in series with a mechanical thermostat in my cylinder, the overshoots are limited to about 62oC and so no-one in the house seems to mind very much. The water just seems a bit hotter than usual for a while. I am sure no customer would call their installer to get anything changed just because of that and so installers are unlikely to be aware of this shortcoming. I maintain that the CS92 is a poor piece of kit and I wish Honeywell would produce a mains-powered replacement that could give more frequent and regular signals to the controller. I would not trust my CS92 on its own to control my hot water temperature.
I've just checked, and I have one overshoot (11 degrees over) in the past 7 days, and a couple of days ago when I checked I had a couple of errors from the hot water sensor (haven't correlated them, and I cleared the log so it's too late). I'd say it's probably happening to a lot of people who just don't notice it.